1. Properties of Seawater
Systems II Lab
Properties of Seawater

2. Salt content (salinity) of seawater
About 3.5% of average seawater consists of dissolved salts
If these precipitated, they would form a layer about 56 m thick on the seafloor
Average salinity is 33 to 37 per mil
Principally sodium, chlorine and six other ions derived from
Dissolved load in streams
Volcanic volatiles carried by atmospheric water
Submarine volcanism
Aeolian dust
Pollutants

3. Salinity of ocean water is related to
Latitude
Evaporation
Precipitation of rain and snow
Inflow of fresh river water
Freezing of sea ice

5. T-S Plots for Various Ocean Waters

8. Ocean Circulation
Surface ocean currents are broad, slow drifts of surface water caused by friction between the ocean and air flowing over it
m deep
Solar radiation provides heat energy, non uniform heating generates winds, which drive the movement of surface ocean water
Ocean current direction is also influenced by the Coriolis force

9. Ocean Circulation

10. Ocean Circulation Ekman transport
The balance of the wind on surface water and Coriolis force at depth
Generates a spiraling current pattern
Results in a net direction of water movement about 90˚ to the wind direction
Near coasts this leads to vertical movement of ocean water
Upwelling if net transport is away from land
Downwelling if net transport is toward land

11. Ocean Circulation

12. Ocean Circulation

13. Ocean Circulation
With geography, ocean current drivers set up the major surface current systems in the world ocean
Each major ocean current is part of a large subcircular current system called a gyre
2 in the Pacific
2 in the Atlantic
2 in the Indian

14. Ocean Circulation

15. Ocean Circulation

16. Ocean Circulation

17. Ocean Circulation